<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>圆角边框</title>
    <style>
      div {
        width: 350px;
        text-align: center;
        border: 2px gray solid;
        padding: 10px 40px;
        border-radius: 25px;
        -moz-border-radius: 25px; /* 旧的火狐浏览器 */
      }
    </style>
  </head>
  <body>
    <div>border-radius 属性允许您向元素添加圆角。</div>
  </body>
</html>
